光学的に活性なポリ (メチルメタクリlate) ステレオ複合体のヘリックスセンスの制御された合成
Takehiro Kawauchi1, Atsushi Kitaura, Jiro Kumaki
1Yashima Super-structured Helix Project, Exploratory Research for Advanced Technology, Japan Science & Technology Agency, Japan. kawauchi@tutms.tut.ac.jp
Journal of the American Chemical Society
|August 15, 2008
まとめ
光学的に活性なポリ (メチルメタクリlate) ステレオコンプレックスは,フラーレン包装のシンディオタクティック PMMA ヘリックスに,イソタクティック PMMA を含めることで形成された. これにより,マクロ分子ヘリシティメモリが保存された三連鎖のヘリックスが生まれた.
科学分野:
- ポリマー化学のポリマー化学について
- 超分子化学 超分子化学
- カイロプティカルスペクトロスコピー
背景:
- 光学的に活性なポリマーは,ユニークなカイロプティカル特性を発揮します.
- マクロ分子ヘリシティメモリにより,ポリマーは特定の螺旋形状を保持できます.
- フラーレンの封じ込めは,ポリマー構造をテンプレートすることができます.
研究 の 目的:
- 光学的に活性なポリ (メチルメタクリlate) ステレオ複合体を準備するために.
- ヘリックスセンスの制御された超分子インクルージョンを調査するために.
- 三連鎖の螺旋構造の形成を調査する.
主な方法:
- 光学的に活性でフルレンに封じ込められたシンディオタキシカルPMMAの合成.
- フラーレン-PMMA複合体内の同質PMMAの超分子含有.
- 振動型円形二重化 (VCD) スペクトロスコーピーを用いた分析.
- VCDスペクトルの計算分析.
主要な成果:
- 光学的に活発なPMMAステレオ複合体の準備が成功しました.
- アイソタクティックPMMAは,シンジオタクティックPMMAヘリックス内の封装フラーレンを置き換えました.
- イソタクティック PMMAによる二重ヘリクスの形成は,シンジオタクティック PMMA の単一ヘリックスと同じハンドネスを持つ.
- トポロジカルな三連鎖ヘリックス構造の証拠.
結論:
- 制御された螺旋構造を持つステレオコンプレックスを作成するための新しい方法を実証しました.
- 三連鎖PMMAヘリでマクロ分子ヘリシティメモリ効果を確立しました.
- ポリマーの自己組み立てを指示するフラーレンのテンプレートの役割を強調した.
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